Molecular and Cellular Biochemistry

, Volume 295, Issue 1, pp 9–17

Small heat shock protein Hsp20 (HspB6) as a partner of 14-3-3γ

  • Ivan S. Chernik
  • Alim S. Seit-Nebi
  • Steven B. Marston
  • Nikolai B. Gusev
Article

DOI: 10.1007/s11010-006-9266-8

Cite this article as:
Chernik, I.S., Seit-Nebi, A.S., Marston, S.B. et al. Mol Cell Biochem (2007) 295: 9. doi:10.1007/s11010-006-9266-8

Abstract

Interaction of human 14-3-3γ with the small heat shock protein Hsp20 was analyzed by means of size-exclusion chromatography and chemical crosslinking. Unphosphorylated Hsp20 and its mutant S16D mimicking phosphorylation by cAMP-dependent protein kinase did not interact with 14-3-3. Phosphorylated Hsp20 formed a tight complex with 14-3-3 in which dimer of 14-3-3 was bound to dimer of Hsp20. 14-3-3 did not affect the chaperone activity of unphosphorylated Hsp20 but increased the chaperone activity of phosphorylated Hsp20 if insulin was used as a model substrate. Estimation of the effect of 14-3-3 on the chaperone activity of Hsp20 with other model substrates was complicated by the fact that under in vitro conditions isolated 14-3-3 possessed its own high chaperone activity. Taken into account high content of Hsp20 in different muscles it is supposed that upon phosphorylation Hsp20 might effectively compete with multiple protein targets of 14-3-3 and by this means indirectly affect many intracellular processes.

Keywords

small heat shock proteinsphosphorylation14-3-3chaperone activity

Abbreviations

14-3-3γ

γ-isoform of recombinant human 14-3-3 protein

DMS

dimethylsuberimidate

DTT

dithiothreitol

Hsp20

recombinant small heat shock protein with apparent molecular mass 20 kDa

pHsp20

Hsp20 phosphorylated by cAMP-dependent protein kinase

S16D mutant of Hsp20

mutant with replacing Ser16 by Asp

PMSF

phenylmethanesulfonyl fluoride

sHsp

small heat shock proteins

Copyright information

© Springer Science+Business Media, Inc. 2006

Authors and Affiliations

  • Ivan S. Chernik
    • 1
  • Alim S. Seit-Nebi
    • 1
  • Steven B. Marston
    • 2
  • Nikolai B. Gusev
    • 1
  1. 1.Department of Biochemistry, School of BiologyMoscow State UniversityMoscowRussia
  2. 2.Imperial CollegeSchool of Medicine at National Heart and Lung InstituteLondonUK